Spondylolisthesis is a back condition in which the vertebra (the spine) slips forward relative to the vertebra above and/or below it. L4-5 indicates the level of the spine in which the bone is slipping forward. The lumbar spine (designate by the letter "L") is the lower part of your spine. There are 5 lumbar vertebrae.The grade tells us how much of the bone has moved. Grade 1 = 25% of the vertebral body (bone) has slipped forward. Degeneration means that the bone has slowly deteriorated and worn away. This often occurs as a result of age and/or overuse.
In your case grade 1 degenerative spondylolisthesis at L4-5 = the vertebral body (bone) at the L4-5 level of your lower back has slipped forward 25% most likely as a result of wearing away of the bone.
Spondylolisthesis can cause pain in the lower ack, radiating pain/discomfort in the legs, and possible weakness in the legs/changes in walking. Treatment varies from physical therapy to injections (which it looks like you hve one) and possibly surgery. This needs to be discussed and determined by your doctor.
I hope this information is helpful. You can find more information here: http://www.spineuniverse.com/displayarticle.php/article114.html
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